EMPIRICAL RELATION OF SURFACE VELOCITY OF DEBRIS FLOW IN JIANGJIA RAVINE
Zhou Bifan Mu Pinghua You Yang Cheng Zunlan (Institute of Mountain Hazards and Environment,Chinese Academy of Sciences& Ministry of Water Conservancy)
According to physical features of debris flow In Jiangjia Ravine the balance expression of forces of moving debris folw is wretten asFrom it characteristic parameters of moving debris flow are selected as Uc,Hc,pc,and U., U = (Hc g Ic)1/2. So movement function of debris flow is established asf(Uc, Hc,γy,pc, U)= 0. Through dimension analysis, the velocity relation of debris flow is-obtained asWhere Ucis he surface velocity,γyis the lost Specloalm gravity of soll in debris flow,Hcis the depth of debris flow, g is the acceleration of gravity,π is the dimensionlessm product of the characteri stic parameters, γcis the special gravity of debris flow, and Icis the gradient of bed. The π of debris flow in Jiangjia Ravine is determined by flow experiments in a flume. Checking up with data obtained from modelling test and field observation, the empirical relation of surface velocity of debris flow is gutie accorded wth practical cases. It seems to be reflection of movement law of debris flow in Jiangjia Ravine.